Jadwiga Ambroszkiewicz1, Magdalena Chełchowska2, Katarzyna Szamotulska3, Grażyna Rowicka4, Witold Klemarczyk5, Małgorzata Strucińska6, Joanna Gajewska7. 1. Screening Department, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: jadwiga.ambroszkiewicz@imid.med.pl. 2. Screening Department, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: magdalena.chelchowska@imid.med.pl. 3. Department of Epidemiology and Biostatistics, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: katarzyna.szamotulska@imid.med.pl. 4. Department of Nutrition, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: grazyna.rowicka@imid.med.pl. 5. Department of Nutrition, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: witold.klemarczyk@imid.med.pl. 6. Department of Nutrition, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: malgorzata.strucinska@imid.med.pl. 7. Screening Department, Institute of Mother and Child, Kasprzaka 17A, 01-211 Warsaw, Poland. Electronic address: joanna.gajewska@imid.med.pl.
Abstract
BACKGROUND & AIMS: Measurements of bone mineral density (BMD) reflect bone status but not the dynamics of bone turnover. Biochemical markers, which show global skeletal activity, were validated for the assessment of bone formation and resorption processes. Adipokines also play a significant role in the regulation of bone metabolism. OBJECTIVE: To assess body composition, bone mineral density, bone turnover markers and adipokine levels in relation to vegetarian and omnivorous diets. METHODS: The study included 53 vegetarian and 53 omnivorous prepubertal healthy children matched for age and sex (median age 7.0 years). Body composition and BMD were assessed by dual-energy X-ray absorptiometry. 25-hydroxyvitamin D and parathormone levels were measured by chemiluminescence method. Serum carboxy-terminal propeptide of type I collagen (CICP), total osteocalcin (OC) and its forms carboxylated (c-OC) and undercarboxylated (uc-OC), C-terminal cross-linking telopeptide of collagen type I (CTX), leptin and adiponectin levels were determined using immunoenzymatic assays. RESULTS: Both groups of children were comparable in terms of body composition, except for the percentage of fat mass, which was lower (19.24 vs. 21.77%, p = 0.018) in vegetarians. Mean values of total BMD z-score and lumbar spine BMD z-score were lower (-0.583 vs. -0.194, p = 0.009 and -0.877 vs. -0.496, p = 0.019, respectively) in vegetarians compared with omnivores. Serum leptin level was about 2-fold lower (1.39 vs. 2.94 ng/mL, p < 0.001) in vegetarians, however, adiponectin concentration was similar in both groups. Vegetarians had similar concentration of 25-hydroxyvitamin D, but higher parathormone (40.8 vs. 32.1 pg/mL, p = 0.015) and CTX (1.94 vs. 1.76 ng/mL, p = 0.077) levels than omnivores. Total osteocalcin and CICP concentrations were comparable in both groups, however, c-OC/uc-OC ratio was higher (1.43 vs. 1.04 ng/mL, p < 0.05) in vegetarians. We found positive correlation between c-OC and nutritional parameters adjusted for total energy intake (plant protein, phosphorus, magnesium and fiber intakes) in vegetarian children. CONCLUSIONS: Prepubertal children on a vegetarian diet had significantly lower total and lumbar spine BMD z-scores, but absolute values of bone mineral density did not differ. BMD z-scores did not correlate with bone metabolism markers and nutritional variables, but were positively associated with anthropometric parameters. Lower leptin levels in vegetarian children reflect lower body fat. Longitudinal studies are necessary to evaluate the impact of the observed association on bone health at adulthood.
BACKGROUND & AIMS: Measurements of bone mineral density (BMD) reflect bone status but not the dynamics of bone turnover. Biochemical markers, which show global skeletal activity, were validated for the assessment of bone formation and resorption processes. Adipokines also play a significant role in the regulation of bone metabolism. OBJECTIVE: To assess body composition, bone mineral density, bone turnover markers and adipokine levels in relation to vegetarian and omnivorous diets. METHODS: The study included 53 vegetarian and 53 omnivorous prepubertal healthy children matched for age and sex (median age 7.0 years). Body composition and BMD were assessed by dual-energy X-ray absorptiometry. 25-hydroxyvitamin D and parathormone levels were measured by chemiluminescence method. Serum carboxy-terminal propeptide of type I collagen (CICP), total osteocalcin (OC) and its forms carboxylated (c-OC) and undercarboxylated (uc-OC), C-terminal cross-linking telopeptide of collagen type I (CTX), leptin and adiponectin levels were determined using immunoenzymatic assays. RESULTS: Both groups of children were comparable in terms of body composition, except for the percentage of fat mass, which was lower (19.24 vs. 21.77%, p = 0.018) in vegetarians. Mean values of total BMD z-score and lumbar spine BMD z-score were lower (-0.583 vs. -0.194, p = 0.009 and -0.877 vs. -0.496, p = 0.019, respectively) in vegetarians compared with omnivores. Serum leptin level was about 2-fold lower (1.39 vs. 2.94 ng/mL, p < 0.001) in vegetarians, however, adiponectin concentration was similar in both groups. Vegetarians had similar concentration of 25-hydroxyvitamin D, but higher parathormone (40.8 vs. 32.1 pg/mL, p = 0.015) and CTX (1.94 vs. 1.76 ng/mL, p = 0.077) levels than omnivores. Total osteocalcin and CICP concentrations were comparable in both groups, however, c-OC/uc-OC ratio was higher (1.43 vs. 1.04 ng/mL, p < 0.05) in vegetarians. We found positive correlation between c-OC and nutritional parameters adjusted for total energy intake (plant protein, phosphorus, magnesium and fiber intakes) in vegetarian children. CONCLUSIONS: Prepubertal children on a vegetarian diet had significantly lower total and lumbar spine BMD z-scores, but absolute values of bone mineral density did not differ. BMD z-scores did not correlate with bone metabolism markers and nutritional variables, but were positively associated with anthropometric parameters. Lower leptin levels in vegetarian children reflect lower body fat. Longitudinal studies are necessary to evaluate the impact of the observed association on bone health at adulthood.
Authors: Małgorzata A Desmond; Jakub G Sobiecki; Maciej Jaworski; Paweł Płudowski; Jolanta Antoniewicz; Meghan K Shirley; Simon Eaton; Janusz Książyk; Mario Cortina-Borja; Bianca De Stavola; Mary Fewtrell; Jonathan C K Wells Journal: Am J Clin Nutr Date: 2021-06-01 Impact factor: 7.045